What to do when Mac file sharing is not working

Deep in macOS System Preferences, there are options that allow you to share files and folders on your Mac with other computers on your network. If you need and use file sharing, you’ll be very well aware of it and probably wonder how you would survive without it. If you don’t use it, you may not even know it exists. However, even these days where it seems almost everything is synced with the cloud, sharing files directly between computers on a network can be very useful. Sometimes, though, file-sharing goes wrong and doesn’t work. Here’s what to do when that happens.

What is file sharing on Mac?

File sharing allows you to share files and folders on your Mac with other Macs or Windows PCs on your network. On older Macs, you can choose whether to enable sharing using Apple’s proprietary file sharing protocol, AFP, or the standard protocol SMB. On newer Macs, you must use SMB. You can also choose whether or not to allow Windows PCs to connect to your Mac.

By default, when you turn on file sharing, the Public user folders for all accounts on your Mac are available for sharing. You can then add more files and folders to make them available from other computers on the network. You can set permissions for specific users, groups, or everyone and dictate whether they are allowed to read, read and write, or are blocked from accessing files.

When you first set it up, the list of users who can access shared files includes only those users created in the Users & Groups pane in System Preferences. However, you can add anyone who is stored in the Contacts app on your Mac.

Once you have added a user and set their permissions, they will be able to access the files and folders you’ve enabled for them from any Mac or, if you’ve set it up, Windows PC on your network.

Tip

If you plan to share all the files on your Mac across a network, you may want to prune the files stored on it first by getting rid of junk files you don’t need. That way, you’re not sharing those junk files over the network. The easiest way to do that is to use CleanMyMac X’s System Junk tool. It scans your Mac looking for junk and, once it’s identified it, allows you to get rid of it with the press of a button. System Junk identifies user cache, system cache files, language files, logs and other files you probably don’t need and don’t want to share. You can download it for free here.

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What to do when Mac file sharing is not working

There are a number of reasons why file-sharing might not work. We’ve set out several scenarios below, along with possible fixes.

1. Shared folder or server doesn’t appear in Finder

If you expect a server or Mac you’re connected to to appear in the sidebar of a Finder window and it doesn’t, do the following:

  1. Open Finder.
  2. Choose the Finder menu, then Preferences.
  3. Select sidebar.
  4. Make sure Bonjour computers and Connected servers are checked.
  5. If you want to see a server you’re connected to appear on the desktop, click General and choose Connected servers.Finder preferences window

2. You can’t log in to a shared computer

You will need to speak to the administrator and ask them to check that you can be given access to the computer and the files and folders you want to access. If you are the administrator, do the following.

  1. Launch System Preferences and select the Sharing pane.
  2. Make sure File Sharing is checked.File sharing settings
  3. Ensure the folder you want to access is in the list of shared folders. If not, press the ‘+’ and add it.
  4. Is your username in the list of Users? If not, press ‘+’ and add it, then type in a password.

3. You’re denied permission to access a folder

As we explained above, file sharing on the Mac is built on Unix, which uses a system of permissions. If you can’t access the file or folder you need, it’s likely a permissions issue. Files in a shared folder don’t automatically inherit the same permissions as the folder. To apply permissions granted to a folder to all the files in it, right-click on the folder in System Preferences > Sharing and choose ‘Apply Permissions to Enclosed Items’.

How to show shared folders in Finder

To set permissions for a shared folder, select it in the ‘Shared Folders’ panel in the Sharing pane of System Preferences, then click your username in the right-hand panel and click the arrows to choose permissions.

If you’re trying to connect from a Windows PC, click Options in the main Sharing window, check the account's name that houses the file or folder you want to share, and press Done.

File sharing on Mac is a handy tool if you have multiple Macs or Macs and PCs on a network. Most of the time, once it’s set up, it just works. Occasionally, however, it goes wrong, and you either can’t connect to a Mac on the network or can’t access the folder you need. If that happens to you, follow the steps above, and file-sharing will be working properly again in no time.

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